1. Field of the Invention
The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus capable of effectively forming a quality image without causing problematic phenomena such as a vermiculate-like false image and a curled-up cleaning blade.
2. Discussion of the Related Art
A related art electrophotographic color image forming apparatus employing an intermediate transfer member transfers primary separate color toner images formed on a plurality of image carrying members sequentially onto the intermediate transfer member at a position into a color image. The color image intermediately formed on the intermediate transfer member is then transferred onto a recording medium. In such an image forming apparatus, the plurality of image carrying members are of photoconductive. Also, the intermediate transfer member includes a belt extended between a plurality of rollers. Each of the primary image transfer from the image carrying member to the intermediate transfer member and the secondary image transfer from the intermediate transfer member to a recording medium is conducted by generating an electric field.
The above-described related art image forming apparatus has a problematic nature to cause a vermiculate image, i.e., a part of a tone image is not sufficiently transferred during the primary image transfer process. As a result, an image has a relatively low density or a density drop in a vermiculation-like shape, particularly around a middle portion of the image. For example, to address this problem, it is needed to apply a lubricant to the image carrying member to reduce a friction coefficient of a surface of the image carrying member so as to reduce an attraction force between the surface of the image carrying member and the toner.
However, the friction coefficient acted between the surface of the image carrying member and the toner relates not only to the nature of image transfer but also to another problematic phenomenon called a curled-up cleaning blade. To address this problem of curled-up cleaning blade, coating a lubricant is also effective. Therefore, suitable conditions for lubricant coating and friction coefficient are needed to address these two problems at the same time.
Currently, there is no image forming apparatus that is provided with an effective mechanism to eliminate the above-described problems at the same time.